The organization announced Monday that the two actors will be honored at its 23rd annual Environmental Media Awards this fall.
Damon will receive the Ongoing Commitment Award for his work with Water.org, the organization he co-founded that aims to bring safe water and sanitation to people around the world.
The 42-year-old actor says he hopes the award brings attention to Water.org's efforts "to bring clean water to communities around the world and inspire new friends and partners to join the fight."
Panettiere will accept the Futures Award, which recognizes younger entertainers for their potential to be environmental activists. The "Nashville" star is active with the Whaleman Foundation, an oceanic research and conservation group.
The 24-year-old actress said she's excited to talk about her work with the Whaleman Foundation and "using my voice to protect our oceans and their amazing inhabitants."
The prizes will be presented at a ceremony on Oct. 19 at Warner Bros. studios in Burbank, Calif.